Process for the manufacture of metal pyrophosphate casein compounds colloidally soluble in dilute alkaline solutions



I phosphoric acid albumm compounds known th UNITED sures PATENT OFFICE.

ALBERT FREY, BASEL, SWITZERLAND CHEMICAL WORKS, 013

,ASSIGNOR TO THE HOFFMANN-LA ROCHE NEW YORK, N. Y., A CORPORATION OF NEWYORK.

Be it known that I, ALBERT FREY, a citizen of Switzerland, and aresident of Basel, zerland, have invented certain new and usefulImprovements in Processes for the Manufacture of Metal PyrophosphateCasein Compounds Colloidally Soluble in Dilute Alkaline Solutions, ofwhich the following tak 1s a specification. U I E y invention relates toa new process for the manufacture of metal pyrophosphate caseincompounds colloidally soluble in dilute alkaline solutions, whichconsists in dis solving casein in alkali pyrophosphate and addinganother metal salt to this solution. Compounds which contain albumin,phosphoric acid and metals have already been used for therapeuticpurposes. In view of the use" they are put to, such products should equite easily soluble in alkali, because in such case only theirabsorption in the intestinal alkaline juice is assured. The metalheretofore meet these requirements not at all, or only partially. v

According to the processes known heretofore relating to the manufactureof metal phosphoric acid albumin compounds, casein 1s for instancedissolved in alkali and the alkaline solution treated with sodiumphosphate and solutions of metal salts. In one instance it has beenproposed to completely saturate the acid valences of casein by taking itup in an excess of alkali or alkaline earth, and to combine themetaphosphoric acid with the albumin molecule by adding metaphosphoricacid to the alkaline solu-, tion. Another processalready known describesin a similar manner the manufacture of tricalcium phosphate albumincompounds.

disadvantage products which are not soluble 0th these of yielding inalkali. In-order processes have the to render the products more easilysoluble in alkali, it has been recommended touse greatly dilutedsolutions, but this is unfavorable in practice. It has further beenproposed to use pyrophosphoric acid and its salts for the manufacture 0calciumand iron-phosphoric acid al-' bumin compounds, soluble in alkali;here solubility Specification of Letters Patent.

' poses.

, tion of 112 ,cipitated by adding alcoho Patented June 14, 1921.

have the disadvantage of containing little phosphoric acid, which nodoubt is to the addition of free alkali when combi11- mg the phosphoricacid with the albumin molecule. In the new process, casein, withouthavmg previously been dissolved in alkali, is

en up in a solution of alkali pyrophosphate and another metal salt addedto the solution. The resulting product meets all requlrements. By thesimpl solving in alkali pyro nation of phosphoric he mixture shows anacid reaction after the addition of the metal salt, by which fact thetransformation distinguishes itself from the processes known heretofore,which latter erlrliploy an alkaline solution. P

e metal Ewample I.

. 66 parts of casein are dissolved in a soluparts of crystallized sodiumpyrophosphate and 800 parts of water and, while stirring, 156 parts of afour times normal solution of calcium chlorid are added to the mixture.The new compound is pre- After having C. The prodpyrophosphate itssolutions in sodium bicarbonate and dilgfedsolution of sodium carbonateare sta e.

been washed it is dried at Example 2.

6.6 parts of casein are dissolved in a solution of 11.2 parts of sodiumand 120 parts of water and to this 19.5 arts of a 23% solution offerric-chlorid are a ded, w 'le stirring. he compound obtained isprecipitated with alcohol, washed and dried at 50 C It contains 50% offerricphosphate. The product is easily soluble in alkali; the solutionsare stable.

claim: 1. As a new article of manufacture the pyrophosphate 10 whichcomprises metal pyrophosphate casein compounds colloidally soluble indilute alkaline solutions, which are entirely soluble in alkali; thesolutions of this'compound in sodium bicareonate and diluted solutionsof sodium car- 4 leonate are stable.

2. llhe process for the manufacture of metal pyrophosphate caseincompounds colloidally soluble in dilute alkaline solutions dissolvingcasein in alkali v memes pyrophosphate adding a metal salt to thissolution and precipitating the compound thus produced.

In witness whereof I have hereunto set my hand.

ALBERTFREY;

Witnesses Harmon Knnm, HUBERT Ramon.

